Help With Toolpath Verification

[oldtbone55]

@LibertyMachine

Hello Seth, 

I'm asking for your help with the CAM operations for a guitar neck that I've just finished modeling as you've been such a great help to me before. I've created the toolpaths but need someone to give them a quick review to see if there's anything wonky or if I could improve any of the toolpath operations. It looks like there's no way to create tabs for a 3D contour like there is for a 2D contour so I only have tabs on one end of the neck. Do I have to create tabs as part of the model for the headstock to get around this problem or is there another way? I've attached my file.

Your help is greatly appreciated. Thanks.

[daniel_lyall]

Good spotting that is what the problem is it's sitting at the guitar body's Zero not the jigs Zero.

Add the jig to the stock selection in the setup and it corrects itself, also make sure you keep the jig as the fixture so it names what it's crashing into if it does.

The toolpaths are not regenerating properly for me at the moment, I think it's my computer I will post back your file when I get it sorted.

[daniel_lyall]

@oldtbone55 I got it sorted.

Just adding the jig to the stock selection is the cure.

But what I found it was stopping the rest machining working and it would not gen a toolpath at all, what I had to do if this happens to you as well, turn rest machining of regen all toolpaths if it still being silly reselect the model in the toolpath then regen the toolpaths.

If they all re generate, go back in and select rest machining for the two parallel toolpaths, then it should work, just leave them for 5 mins that's how long I had to wait, It may be just my computer playing up.

If everything regens fine when you just add the jig to the stock can you let me know then It is my computer playing up if you have problems as well it may be a bug.

example attached.

[oldtbone55]

@daniel_lyall

Hello Daniel, adding the jig stock to the setup did fix the problem with the location of the bottom of the stock. I did have to remove the rest machining from the two parallel operations in order for a toolpath to be generated but when I tried to add the rest machining back and re-generate the toolpath it would'nt create a toolpath. I don't think there's anything wrong with your computer. Mine was doing the same thing as yours, taking forever to generate toolpaths. It even caused Fusion to shut down. Is this model really that complex to cause this or could it be just the way the toolpaths are set up? I ran your example and it too was getting crashes into the fixture and stock. I thought we had fixed this when we made the jig smaller? One other thing I tried was to use the avoid/surface option for the parallel toolpaths by picking the jig body. Unfortunately it was taking forever when I tried to re-generate the toolpaths and eventually Fusion just closed up. I'm going to try again when I get Fusion opened again. Did you get any crashes on your end when you made the changes?

Thanks.

[oldtbone55]

@daniel_lyall

Hey Daniel, I tried running a sim for setup 3 and Fusion crashed again. I've sent the error report to Fusion (this is the 2nd one). I hope they'll look into this and provide an answer. Off hand I'd say that Fusion was having a problem because the stock setup contains two bodies. Is Fusion crashing for you when you try and run a sim?

Thanks.

[daniel_lyall]

No crashes, they must of stuffed something up in the last update last weekend your file was fine, the only differences is the name, I will try a few things to see if I can find the what.

[daniel_lyall]

ops wrong post

[daniel_lyall]

Turning the timeline off makes next to no differences to how long stuff takes to generate, it's in the rest machining where the problem is, even the file from last week is now slow and failing.

this is going to be a fun bug report to do

[oldtbone55]

@daniel_lyall

Hey Daniel, I've sent in three reports for the 3 times that Fusion clamed up on me when I tried to run a simulation for Setup 3. The only thing that's changed in the setup is the addition of the jig body to the solid stock. I wasn't having any issues prior to this. I've posted the problem on the support forum and have received a reply that the same thing is occurring on their end. They think the problem is stemming from my design but haven't figured out why yet. Sure hope they can figure this out. Without the jig the neck would be dangling in mid-air when the underneath portion is machined and I'm not sure it could take the stress from the mill.

Cheers!

[daniel_lyall]

It's the rest machining what's doing it take that off all toolpaths in setup 3 and it works fine or as it should for the toolpath generating, the sim is still bad. spinning wheel for 5 mins now.

What I will do is convert the file to DM, then strip it and put each part in it's own component in it's own file then do a linked component assembly, this removes all dependencies so the don't get recalculated each time a change is done, it should speed it right up doing this.   

[oldtbone55]

@daniel_lyall

Thanks Daniel. I wouldn't know how to do what you're going to do. 

[oldtbone55]

@daniel_lyall

Hello Daniel, thanks for your reply. I've attached the file for you to work with. Fusion has been a bear this week. Sure hope things get better. As I said in my e mail, I'm trying to create a slot in the neck for the truss rod to be installed. The slot needs to be 0.375" deep by 0.250" wide by 14.25" long. Your help is greatly appreciated.

Best Regards.

[daniel_lyall]

@oldtbone55 will do 

[daniel_lyall]

@oldtbone55 does it go on the bottom faces, if it is it's the angle that it is on where the problem is (it's the same with the top) if you places a plane at angle on it so it's squire to then do a offset plane from the plane at angle above the model then you can sketch the shape on the plane then extrude it down and cut the section you want remove out.

How I worked out the angle I sketched a line along the top (long white line above) then sketch the other two lines and set them horizontal/vertical to get the angle the long white line is on.

That's the easy way to get the plane squire 2 you can eyeball it as well that being rough thoe.   

The offset plane does not need to be as high as it is in the pick

[oldtbone55]

@daniel_lyall

Hey Daniel, the slot goes on the top face which is the flat side. Maybe I'm wrong but I thought that you could sketch on a face but that isn't working. What you're saying is to create an offset plane, sketch the slot shape, project it to the surface of the neck, then cut the slot out with the extrude command. Have I understood correctly?

Thanks.

[daniel_lyall]

Not totally if its a angled faces it wont always be useable so you have to use a plane to get squire to plane then use an offset plane to put the sketch on other wise it's a 3D sketch.

I cant even select the flat faces to put the sketch on it it needs a plane tangent to faces at point to placed on it for it to work how I said to do it before it works if you just use the plane tangent to faces at point to get the squire to then do a offset plane to be able to sketch it in 2D.

You can not diamention 3D sketch's after you set them if you forget to set the diamention you have to try again.

To make it so you can do the sketch in 2D you need something to pick that you can get a offset plane off, what is in this case is the plane tangent to faces at point.

@jeff_strater When you have a spare second can I get you to explain all this properly I don't know the why just how to get around it, tony likes get the why and how to  Thank you

Jeff will be able to explain it better than I ever could.

[oldtbone55]

@daniel_lyall

Hey Daniel, thanks kindly for the explanation. I created a construction plane at an angle based on the top of the sketch of the neck then sketched the slot onto it. Then I used the press/pull command and did a cut the depth that I require. It worked except than when I did the press/pull the cut only worked on a portion of the sketch. I then remembered that I had run into this problem with my very first attempt on the original model I had created. This model had a lot of issues because of the number of creases in it having very poor topology. I didn't really understand just how t-splines should be used. The fix at that time was to extrude the cut in both directions (I still don't understand why or how that works). I did that with the current model and now I have the slot that I wanted. 

@jeff.starter -   I believe that you provided me with the solution to this. I'm sure that my current body is way better than the original one but if you could have a look at the file and provide some feedback it would be appreciated. 

Thanks Guys.

[oldtbone55]

@daniel_lyall

Hello Daniel, I'm unable to create a toolpath for the slot and can't figure out why. I've attached my file with the slot that was created for the truss rod.

Thanks.

[daniel_lyall]

Will do

[daniel_lyall]

With toolpaths they all are built to a purpose, like 2D Adaptive is for removing material as fast as possible within a defined area what most times has a flat bottom, 3D Adaptive is the same but from the model's surfaces minus the stock what just means it knows most times to remove the stock not the model inside the stock and it has a flat bottom.

Now to your model what you remove in op 2 to op 4 is removing the material as fast as possible from an open area so a Adaptive works very well here, (open area is the key)

Then a 2D contour around a selected area what is controlled by the selection and the cutting direction it has a flat bottom.

Then we come to the hole with a closed bottom, what can also be called a pocket, then instantly you think that's a pocket and it's a pocket with a angled bottom, now here comes the deciding factor is it in 2D or 2.5D or 3D (2.5D just means one axis will be move differently to the other axis) now because it has a angle to it with squire to each other sides it's a 2.5D shape.

(Looking and knowing what toolpaths to use when and where is just what is it, is it angled is it open or closed it takes time to learn this)

so the first thing I tried was the 2D pocket nup that's out it does not wont to go along the angle surfaces then 3D will work and it does because it's a 2.5D pocket.

I have added options for you they all do the job of removing the material but only roughing it out, to finish it you need a toolpath what will stick to the bottom contour like glue a traces toolpath will do it as it's job is to stick to a contour or sketch line like poo to a blanket.

Example attached.

those US army drone are nosey things 

[oldtbone55]

@daniel_lyall

Hey Daniel, thanks for the information and the example. I looked at each one and then decided to use the pocket IDEA 2 toolpath. It required the shortest amount of machining time and worked perfectly. I've been working on machining the neck and ran into a couple of issues. The op2 stock that's used to create the jig and the op2 stock that fit together to perform op3 have interference issues and won't fit together. I can get around this by sanding off some material from the jig but would prefer to have this done when the jig is machined. What would be the best way to do this? Should I re-sketch those faces and then move the sketch lines in a bit or can it be done when setting up the toolpath operation? The one thing that I've found out is that it is critical that both the jig and op2 stock centerlines stay perfectly aligned. With my first attempt the op2 stock was skewed a bit and of course the top of the neck didn't get machined evenly on both sides.

My second question is, how do you make sure that the stock you're going to machine is lined up with the machine head X-axis travel? I was using the waste board edges but it turns out that the waste board isn't necessarily aligned with the machine head. I then tried scribing a line down the center of the stock using a brad point bit inserted in the machine head. This did help as it turned out the stock wasn't lined up with the machine head x-axis using the method I described above. Is there another way that doesn't take as much time? I've asked the shop if they could machine grid lines on the waste board as a guide.

Thanks again.